This disclosure is directed to devices, systems, and techniques for dynamically adjusting a bio impedance measurement range. An example device includes a plurality of electrodes. The device also includes sensing circuitry configured to sense a bio impedance and processing circuitry. The processing circuitry is configured to apply an excitation signal to the sensing circuitry and, based on the application of the excitation signal, determine a sensed bio impedance value within a bio impedance measurement range. The processing circuitry is also configured to determine whether the sensed bio impedance value is within a predetermined portion of the bio impedance measurement range for a predetermined period of time and based on the sensed bio impedance value being within the predetermined portion of the bio impedance measurement range for the predetermined period of time, adjust the excitation signal.

A medical device can be localized by providing at least three non-colinear localization elements (e.g., electrodes) thereon. Once placed in a non-ionizing localization field, three adjacent localization elements, at least one of which will typically be a spot electrode, may be selected, and the non-ionizing localization field may be used to measure their locations. A cylinder is defined to fit the measured locations of the selected localization elements. The cylinder is rotationally oriented using the measured location of a spot electrode. Location and rotational attitude information may be used to construct a three-dimensional representation of the medical device within the localization field. The electrodes may be provided on the medical device or on a sheath into which the medical device is inserted. The invention also provides systems and methods for identifying and calibrating deflection planes where the medical device and/or sheath are deflectable.

Described here are wireless monitoring devices, systems, and methods for estimating one or more physiological parameters of a patient. These devices and systems may measure or receive a signal waveform transmitted through one or more of fluid and a physiological structure of a patient. This measured signal waveform may be processed to generate waveform parameter data used to estimate a physiological parameter such as blood velocity, heart wall thickness, and the like.

This disclosure is directed to a catheter having a basket-shaped electrode assembly with a high electrode density. The basket-shaped electrode assembly may have a plurality of spines, such as up to twelve, each with a plurality of electrodes, such as up to sixteen. The distal ends of the plurality of spines are joined at a distal hub, all of which are fashioned from a single piece of superelastic material.

A medical device can be localized by providing at least three non-colinear localization elements (e.g., electrodes) thereon. Once placed in a non-ionizing localization field, three adjacent localization elements, at least one of which will typically be a spot electrode, may be selected, and the non-ionizing localization field may be used to measure their locations. A cylinder is defined to fit the measured locations of the selected localization elements. The cylinder is rotationally oriented using the measured location of a spot electrode. Location and rotational attitude information may be used to construct a three-dimensional representation of the medical device within the localization field. The electrodes may be provided on the medical device or on a sheath into which the medical device is inserted. The invention also provides systems and methods for identifying and calibrating deflection planes where the medical device and/or sheath are deflectable.

A method includes receiving, from a probe that includes electrodes and is positioned inside a cavity in an organ of a patient, (i) proximity signals indicative of proximity of the electrodes to a wall of the cavity, and (ii) position signals indicative of positions of the electrodes within the cavity. Based on the proximity signals and the position signals, at least a portion of a volume of the cavity is represented by a sphere model including multiple spheres. A direction is identified along which one or more spheres are larger than one or more surrounding spheres by at least a given factor. Based on the indicated direction, a location of an opening in the wall of the cavity is estimated and presented to a user.

A heart size measuring tool includes a tubular body, a flexible measuring cord having length indicia, a measuring cord support mechanism movable between retracted and extended states with respect to the body, and an actuating mechanism to move the measuring cord support mechanism. When in the retracted state the measuring cord support mechanism is positioned within the tubular body with the measuring cord in a collapsed position. When the measuring cord support mechanism is in the extended state the measuring cord extends around a portion of a heart to be measured. A scale on the body can be used in connection with the indicia on the measurement cord to provide a reading of the heart size.

Disclosed are devices (100), systems (500), and methods for determining the dipole densities on heart walls. In particular, a triangularization of the heart wall is performed in which the dipole density of each of multiple regions correlate to the potential measured at various located within the associated chamber of the heart. To create a database of dipole densities, mapping information recorded by multiple electrodes (316) located on one or more catheters (310) and anatomical information is used. In addition, skin electrodes may be implemented. Additionally, one or more ultrasound elements (340) are provided, such as on a clamp assembly or integral to a mapping electrode, to produce real time images of device components and surrounding structures.

The invention relates to a method for determining at least a flow velocity or a fluid volume flow (5) of a fluid flowing through an implanted vascular support system (1), comprising the following steps: a) carrying out a pulsed Doppler measurement by means of an ultrasonic sensor (2) of the support system (1), b) evaluating a measurement result from step a), which has a possible ambiguity, c) providing at least one operating parameter of a flow machine (3) of the support system (1), d) determining at least the flow velocity or the fluid volume flow (5) using the measurement result evaluated in step b), wherein the possible ambiguity of the measurement result is corrected using the operating parameter.

Embodiments of device for monitoring pressure in the left atrium are provided. The device is delivered to the left atrium via the coronary sinus. A first portion of the device is deployed in the left atrium, the first portion of the device comprising a pressure sensor. A second portion of the device is deployed in the coronary sinus. Monitoring left atrial pressure via coronary sinus access can provide a safer, less invasive way to monitor a patient for heart failure.